Tetris. Arrange the falling blocks to make a complete row from left to right, which then disappears. Ad infinitum.
Designed and programmed by Alexey Pakitnov in the Soviet Union whilst he was working for the Dorodnicyn Computing Centre, Tetris is known and loved the world over, and exists on nearly every single console and computer in some form.
Tetris on the Mega Drive has an interesting story. Some people don’t consider the game to have ever had a proper official release, yet copies of the game are out there and it was assigned a release number.
It all revolves the rights for releasing home computer vs console versions of the game…